Indian Paintbrush (Castilleja) flowers bloom orange on Ninemile Ridge Trail, in the Blue Mountains, Umatilla National Forest, Pendleton, Oregon, USA. Castilleja (Indian Paintbrush or Prairie-fire) is a genus of about 200 species of annual and perennial herbaceous plants native to the west of the Americas from Alaska south to the Andes, plus northeast Asia. These plants are classified in the family Orobanchaceae and are hemiparasitic on the roots of grasses and forbs.